The beater brush will no longer drive under a load on short pile carpet

adjust the setting on the vacuum head to pile or plush carpet
it is a simple lever that raises the hood to allow more air under it to make it easier to push

There is not a setting for hard floors on most Oreck vacuum cleaners. If I were looking at it, my guess would be to check the brush to see if it is still on the new brush setting or if it is on the used brush setting. To figure that out, take out the 5 screws that hold the bottom rug plate on, and look at each end of the brush before you remove it. If you see several "hash" marks on the black plastic part of the bearing, it is still on the "new" setting. Pull the brush out and rotate the bearings at both ends until you see just one "hash" mark and then replace the brush. This puts the brush on the "used" or worn setting. If it is already on that setting, you are in need of replacing your brush. While you have your vacuum opened up, look at your belt to see if it looks worn, if it is "shiny" on the inside surface, I would replace it as well. The only other thing that I could think of that would be causing it to drag on the carpet is if you recently changed carpet and have a thicker pile than what you had before. Oreck does make two different high pile attachments that will fit on the bottom of your machine that will raise it up above the pile, yet still let you vacuum your carpet. Hope this helps.

This sounds like a belt issue to me. The belt usually runs from a drive shaft to the rotating beater bar / brush. Both the drive shaft and beater bar / brush that are contact with the belt must be clean. Oils, etc. can interfere with the grip on the belt. If the belt is squealing for very long, the drive shaft can damage the belt. make sure you're using the correct belt - and have all the parts in their right places. Recheck your work and provide the vacuum make and model if you're unable to get it working properly.

The beater bar on his machine and other dysons dc01,dc07,dc14 is directly driven by the main vacuum motor via a rubber belt(some models have safety clutches). There are no reset switches- the three tabs on the base are to allow removal of the sole plate. If something jams in the beater while operating and left for long enough (about 1 minute) the belt can burn out and need replacement. the belts are cheap, good skill is required to remove the sole plate to install a new belt because they are so tight.

hooked rugs produce the highest amount of friction opposing the brush rotation, which can over heat the drive motor. try using a height setting that raises the brush so that it barely touches the pile. If this issue has been going on for some time, you may need to replace the drive motor.

Brush rolls wear out and usually need replaced every few years. The DC33 model has a clutch with belts which could also be slipping. I would replace both of them

belts will stretch when they slip. There no adjustments on beater-bars. The way to prevent this is to have a height adjustment to be high on high pile and low for low pile rugs.

It seems that your drive belt for the beater brush is stretched. This is a common problem -- if you flip the vacuum over so you are looking at the bottom, you should see several screws holding a faceplate in place. Unscrew these, and you should be able to get access to the beater brush and belt. Pull on the belt a little -- if it has a lot of give, or seems stretched or cracked, replace the belt and your vacuum should be fine. If it is not stretched or cracked, move the belt and look between the belt and where it holds onto the brush (there should be a little groove that the belt is sitting it). If there is a lot of debris or hair (I have long hair and this happens to me quite often) between the belt and the brush bar, clean it out, and you should be good. The squeaking noise leads me to believe that the belt is stretched and could be replaced.

Check to see that the beater brush is not frozen up. Pull the brush and clean it, spraying some WD40 on each end piece that holds the brush in place. Also be sure the belt is properly installed so that the brush turns in the correct direction. If the brush is not turning or not turning in the correct direction, it will not beat the dirt from the carpet so that it can be picked up by the vacuum's suction.

Sounds like you really need a new belt. Don't know why it is taking so long for you to get one. But belts stretch and then won't turn the brush roll under load. Call around to your local repair shops, must will a good selection of belts on hand.